diff --git a/block/ioctl.c b/block/ioctl.c
index 8171858dc8a9d8bcd2d4740a1e6da082309e90ae..7c578f84a4fd9577d3b55e10b61190d9b61f5ca9 100644
--- a/block/ioctl.c
+++ b/block/ioctl.c
@@ -683,7 +683,7 @@ long compat_blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg)
 			       (bdev->bd_bdi->ra_pages * PAGE_SIZE) / 512);
 	case BLKGETSIZE:
 		size = i_size_read(bdev->bd_inode);
-		if ((size >> 9) > ~0UL)
+		if ((size >> 9) > ~(compat_ulong_t)0)
 			return -EFBIG;
 		return compat_put_ulong(argp, size >> 9);